If you lose your wallet, don’t panic.

If you lose your traveler’s checks and you remembered the all-important rule of writing down the check numbers and keeping them in a separate and safe place, you can easily replace them in any big European city. Just call the issuer of your checks for details.

If you lose credit or ATM cards, you’ll need to cancel them immediately. Before you leave on your trip, create a list of the international customerservice numbers given on the back of each card. Keep the list in a safe spot — but not with your cards! Note that these are special U.S. numbers set up explicitly for emergencies abroad. Go to any pay phone in Europe and dial an international operator to connect your collect call. Your credit-card company or insurer may require a police-report number or record of the loss. The collect-call numbers for the most common credit cards include:

- American Express (credit cards or traveler’s checks): 801-945-9450

- Visa (checks): +44-171-937-8091 or 813-623-1709

- Thomas Cook (checks): +44-1733-318-950

Your credit-card or ATM-card issuer may be able to wire you a cash advance or issue an emergency replacement card in a day or two. In situations such as these, carrying traveler’s checks, which are easily replaced, can save your entire vacation, as American Express commercials waste no time trumpeting.

Some major credit cards offer a service (usually for a small fee) in which you can register the numbers of all your major cards (credit, bank, and calling card), and they’ll cancel them for you with one phone call, as well as provide you with emergency cash or traveler’s checks. (You can pick up the traveler’s checks at a local American Express, Thomas Cook, or Western Union office.)

An alternative to gaining quick cash is to have a friend wire you money. Reliable, international services include Western Union (%800-CALLCASH; www.westernunion.com) and American Express’s MoneyGram (800-666-3947; www.moneygram.com), which allows someone back home to wire you money in an emergency in less than ten minutes.

When traveling abroad, you’re a nonentity without your passport. If you lose your passport, go immediately to the nearest U.S. consulate. Make sure that you bring a photocopy of your passport’s information pages (the two pages facing each other with your picture and vital information), passport-sized photos (bring some with you), and any other form of identification that wasn’t lost.

Identity theft and fraud are potential complications of losing your wallet, especially if you’ve lost your driver’s license along with your cash and credit cards. Notify the major credit-reporting bureaus immediately; placing a fraud alert on your records may protect you against liability for criminal activity. The three major U.S. credit-reporting agencies are Equifax (800-766-0008; www.equifax.com), Experian (888-397- 3742; www.experian.com), and TransUnion (800-680-7289; www. transunion.com).